"Mayan Express" Poses Big Weather Risks In. U.S. South This Week

Torrential rains, with up to a foot expected in Louiiana,
are expected in a broad area of the lower Mississippi
Valley this week due to the "Maya Express" Another
zone of heavy, flooding rains are likely from norther
California to Washington. Red, orange, and yellow
zones are most at risk

A lot of us have heard of the "Pineapple Express," a stream of rich tropical moisture from near Hawaii that sometimes crashes into the West Coast, causing huge rains and floods.  

Ever heard of the "Maya Express?" It causes a similar type of problem, only in the southern and eastern United States. The reason I bring it up now because some areas in the South, particularly Louisiana, Arkansas and surrounding states, are under the gun for this so called Maya Express this week.

I'll set the whole thing up: The well-publicized, and welcome rain storms have arrived in California, where flash flood watches are up for many areas today, and several feet of snow are coming down in the Sierra Nevada.

Up to a foot of rain is forecast for parts of northern California over the next seven days. While this isn't technically the Pineapple Express, its still boatloads of rain, for sure. One person has already died in the California flooding, and there have been reports of dangerous mudslides and debris flows. The stormy California weather is expected to continue for the next few days.

One of these California storms is expected to move southeast into northern and central Mexico. Storms don't usually do that, but such a setup is a bit more likely in years with a strong El Nino, like this one.

This storm will set up a rich flow of very wet air from off the east coast of Mexico, from the western Caribbean and push it toward the western Gulf Coast and lower Mississippi Valley. Pieces of that Mexican storm will also move north into Texas, encouraging that south to north flow of wet air northward.

In a Forbes article this week, Dr Marshall Shepherd, Director of the Atmospheric Sciences Program at the Univeristy of Georgia, and host of the Weather Channel's "Weather Geeks" program, says the upcoming weather pattern this week is an example of the "Maya Express"

Shepherd, in Forbes, cites the work of researchers Paul Dirmeyer and Jim Kinter, who examined immense floods in the Midwest in 1993 and 2008. Although numerous factors went into those floods, a primary cause was a rather narrow but intense band of atmospheric moisture moving north from the western Caribbean into the United States.

The researchers dubbed this type of weather pattern the "Maya Express," based on its source region.

The Pineapple Express and the Maya Express are examples of atmospheric rivers, narrow channels of intense moisture that flow like a river, except in the atmosphere. These can obvious cause extreme rainfall events and floods.

Another disaster, the Great Memphis Flood of 2010, was also largely due to the "Maya Express."

So you can see why meteorologists are nervous about places like Louisiana and Arkansas this week. The flooding will probably extend into much of Missouri and on into the southern half of Illinois as well.

Thry've had a lot of wet weather this winter, so rivers are already running high there. Up to a foot of rain is likely later this week from the "Maya Express," so this will only cause a dangerous situation, both with flash floods and large, surging floods in the bigger rivers.

Some of these places that are in the path of the "Maya Express"  had a record wet 2015 and a soggy first month of 2016. They don't need the rain.

A secondary, but real risk from this weather pattern is severe weather and tornadoes. The greatest risk of that happening is in Texas and Oklahoma Monday, eastern Texas and western Louisiana and southwestern Arkansas Tuesday, and in and around Louisiana Wednesday.

Bottom line: Anybody living in the central and southern Plains, and the southern and central Mississippi Valley had better keep an ear toward the forecasts and weather warnings all week. It could get dangerous.